4H-Pyrido[1,2-a]pyrimidin-4-one, 3-[2-[4-[(Z)-(2,4-difluorophenyl)(hydroxyimino)methyl]-1-piperidinyl]ethyl]-6,7,8,9-tetrahydro-2-methyl-

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Remarks:

Type of genotoxicity: gene mutation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2003-12-10 to 2004-01-09

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Remarks:

Only three strains are tested. However, an expert statement is added in attachment and the field "any other remarks" to justify the fact that no further testing is necessary.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2004

Report date:

2004

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

yes

Remarks:

only 3 strains of bacteria used, limited methodology

GLP compliance:

no

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

3-(2-{4-[(Z)-(2,4-DIFLUOROPHENYL)(HYDROXYIMINO)METHYL]PIPERIDIN-1-YL}ETHYL)-2-METHYL-6,7,8,9-TETRAHYDRO-4H-PYRIDO[1,2-A]PYRIMIDIN-4-ONE

EC Number:

603-689-1

Cas Number:

132961-05-8

Molecular formula:

C23H28F2N4O2

IUPAC Name:

3-(2-{4-[(Z)-(2,4-DIFLUOROPHENYL)(HYDROXYIMINO)METHYL]PIPERIDIN-1-YL}ETHYL)-2-METHYL-6,7,8,9-TETRAHYDRO-4H-PYRIDO[1,2-A]PYRIMIDIN-4-ONE

Test material form:

solid: particulate/powder

Specific details on test material used for the study:

Name of test material: T 1624, ((Z)-3-[2-[4-[(2,4-difluorophenyl)(hydroxyimino)methyl]-1-piperidinyl]ethyl]-6,7,8,9-tetrahydro-2-methyl-4H-pyrido[1,2-a]pyrimidin-4-one)
- Physical state: white powder
- Analytical purity: ~100%
- Storage condition of test material: room temperature in the dark
- Other: date received: 2003-12-01

Method

Target gene:

histidine locus

Species / strain

Species / strain / cell type:

S. typhimurium, other: TA98, TA 100, and TA 102

Details on mammalian cell type (if applicable):

not applicable

Additional strain / cell type characteristics:

other:

Metabolic activation:

with and without

Metabolic activation system:

rat liver homogenate metabolising system (10% liver S9 in standard co-factors)

Test concentrations with justification for top dose:

0.5, 1.5, 5, 15, 50, 150, 500, 1500, 5000 µg/plate

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: DMSO
- Justification for choice of solvent/vehicle: no data

Controls

Controls 1

Untreated negative controls:

yes

Remarks:

untreated

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: N-ethyl-N'-nitro-N-nitrosoguanidine at 3 µg/plate on TA100

Remarks:

without S9

Controls 2

Untreated negative controls:

yes

Remarks:

untreated

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: mitomycin C at 0.5 µg/plate for TA102

Remarks:

without S9

Controls 3

Untreated negative controls:

yes

Remarks:

untreated

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 4-Nitroquinoline-1-oxide at 0.2 µg/plate on TA98

Remarks:

without S9

Controls 4

Untreated negative controls:

yes

Remarks:

untreated

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 2-aminoanthracene at 1 µg/plate for TA100

Remarks:

with S9

Controls 5

Untreated negative controls:

yes

Remarks:

untreated

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 1,8-dihydroxyanthraquinone at 10 µg/plate for TA 102

Remarks:

with S9

Controls 6

Untreated negative controls:

yes

Remarks:

untreated

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: benzo(a)pyrene at 5 µg/plate on TA98

Remarks:

with S9

Details on test system and experimental conditions:

METHOD OF APPLICATION: plate incorporation method

Measured aliquots (0.1 mL) of one of the bacterial cultures were dispensed into sets of test tubes followed by 2.0 mL of molten, trace histidine supplemented, top agar, 0.1 mL of the test material formulation, vehicle or positive control and either 0.5 mL of S9-mix or phosphate buffer. The contents of each test tube were mixed and equally distributed onto the surface of Vogel-Bonner Minimal agar plates (one tube per plate).

DURATION
- Exposure duration: 3 days
SELECTION AGENT: histidine

NUMBER OF REPLICATIONS: triplicate

DETERMINATION OF CYTOTOXICITY
- Method: growth of the bacterial background lawn

Evaluation criteria:

no data

Statistics:

no data

Results and discussion

Test results

Species / strain:

S. typhimurium, other: TA 98, TA 100, and TA 102

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Additional information on results:

TEST-SPECIFIC CONFOUNDING FACTORS
Precipitation: No test material precipitate was observed on the plates at any of the doses tested in either the presence or absence of S9-mix.

RANGE-FINDING/SCREENING STUDIES: no data

COMPARISON WITH HISTORICAL CONTROL DATA:
The vehicle control plates gave counts of revertant colonies within the normal range.
All of the positive control chemicals used in the test induced marked increases in the frequency of revertant colonies, both with and without metabolic activation. Thus, the sensitivity of the assay and the efficacy of the S9-mix were validated.
The S9-mix used in both experiments was shown to be sterile. Results for the negative controls (spontaneous mutation rates) were considered to be acceptable. These data are for concurrent untreated control plates performed on the same day as the Mutation Test.

ADDITIONAL INFORMATION ON CYTOTOXICITY:
The test material caused no visible reduction in the growth of the bacterial background lawn at any dose level.

Remarks on result:

other: all strains/cell types tested

Applicant's summary and conclusion

Conclusions:

Interpretation of results:
negative with and without metabolic activation

The test material was considered to be non-mutagenic under the conditions of this test.